1. Field of the Invention
This invention relates to electrical connecting devices for terminating cords, and more particularly, to devices for making electrical connections between cord conductors and terminals which includes cord strain-relief facilities that are maintained in locked engagement with the cord and a housing of the device during, for example, the application of retrograde forces to the cord during use by the customer.
2. Description of the Prior Art
In the telephone industry, increasing use is being made of modular plug type connectors on retractile handset and on straight line cords which are used between the telephone base and a wall terminal block. In the presently used plugs, a terminal is applied to each of a plurality of insulated conductors contained within a jacketed length of a retractile cordage. These terminals are mounted within a dielectric structure which is attached securely to the associated cordage. The dielectric portions of the plugs, which are mounted on both ends of a length of a cordage, cooperate with receptacles in the wall terminal block and in the telephone base to properly align the terminals of the plug with associated terminals within the wall block and the telephone.
In one plug disclosed in U.S. Pat. No. 3,699,498 issued on Oct. 17, 1972 in the names of E. C. Hardesty, C. L. Krumreich, A. E. Mulbarger, Jr. and S. W. Walden, conductors are confined in conductor-receiving troughs formed in a dielectric base by a cover bonded to the base with flat terminals inserted into individual grooves in the base in a side-by-side arrangement with contact portions thereof extending into engagement with the conductors. See also U.S. Pat. No. 3,761,869 issued Sept. 25, 1973 in the names of E. C. Hardesty, C. L. Krumreich, A. E. Mulbarger, Jr. and S. W. Walden.
It would be desirable both from the ease and the cost of manufacturing to construct a one-piece plug, into which a telephone cord end may be inserted and secured and subsequently engaged by terminals moved into terminal-receiving openings in the plug. Such a plug would require jacket and conductor strain-relief facilities which desirably could be moved, subsequent to insertion of a cord end portion, into a locked position to effectively and continuously resist retrograde forces applied to the cord.